ixgbe: Check return value on eeprom reads

This patch fixes the possible use of uninitialized memory by checking the
return value on eeprom reads. These issues were identified by static
analysis. In many cases error messages will be produced so that corrupted
eeprom issues will be more visible.

Signed-off-by: Mark Rustad <mark.d.rustad@intel.com>
Tested-by: Phil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

1 files changed, 45 insertions, 22 deletions

diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_common.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_common.c
index 50e62a2b1a65..b5c434b617b1 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_common.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_common.c
@@ -2740,13 +2740,19 @@ out:
 static s32 ixgbe_get_san_mac_addr_offset(struct ixgbe_hw *hw,
                                         u16 *san_mac_offset)
 {
+	s32 ret_val;
+
 	/*
 	 * First read the EEPROM pointer to see if the MAC addresses are
 	 * available.
 	 */
-	hw->eeprom.ops.read(hw, IXGBE_SAN_MAC_ADDR_PTR, san_mac_offset);
+	ret_val = hw->eeprom.ops.read(hw, IXGBE_SAN_MAC_ADDR_PTR,
+				      san_mac_offset);
+	if (ret_val)
+		hw_err(hw, "eeprom read at offset %d failed\n",
+		       IXGBE_SAN_MAC_ADDR_PTR);
 
-	return 0;
+	return ret_val;
 }
 
 /**
@@ -2763,23 +2769,16 @@ s32 ixgbe_get_san_mac_addr_generic(struct ixgbe_hw *hw, u8 *san_mac_addr)
 {
 	u16 san_mac_data, san_mac_offset;
 	u8 i;
+	s32 ret_val;
 
 	/*
 	 * First read the EEPROM pointer to see if the MAC addresses are
 	 * available.  If they're not, no point in calling set_lan_id() here.
 	 */
-	ixgbe_get_san_mac_addr_offset(hw, &san_mac_offset);
+	ret_val = ixgbe_get_san_mac_addr_offset(hw, &san_mac_offset);
+	if (ret_val || san_mac_offset == 0 || san_mac_offset == 0xFFFF)
 
-	if ((san_mac_offset == 0) || (san_mac_offset == 0xFFFF)) {
-		/*
-		 * No addresses available in this EEPROM.  It's not an
-		 * error though, so just wipe the local address and return.
-		 */
-		for (i = 0; i < 6; i++)
-			san_mac_addr[i] = 0xFF;
-
-		goto san_mac_addr_out;
-	}
+		goto san_mac_addr_clr;
 
 	/* make sure we know which port we need to program */
 	hw->mac.ops.set_lan_id(hw);
@@ -2787,14 +2786,26 @@ s32 ixgbe_get_san_mac_addr_generic(struct ixgbe_hw *hw, u8 *san_mac_addr)
 	(hw->bus.func) ? (san_mac_offset += IXGBE_SAN_MAC_ADDR_PORT1_OFFSET) :
 	                 (san_mac_offset += IXGBE_SAN_MAC_ADDR_PORT0_OFFSET);
 	for (i = 0; i < 3; i++) {
-		hw->eeprom.ops.read(hw, san_mac_offset, &san_mac_data);
+		ret_val = hw->eeprom.ops.read(hw, san_mac_offset,
+					      &san_mac_data);
+		if (ret_val) {
+			hw_err(hw, "eeprom read at offset %d failed\n",
+			       san_mac_offset);
+			goto san_mac_addr_clr;
+		}
 		san_mac_addr[i * 2] = (u8)(san_mac_data);
 		san_mac_addr[i * 2 + 1] = (u8)(san_mac_data >> 8);
 		san_mac_offset++;
 	}
-
-san_mac_addr_out:
 	return 0;
+
+san_mac_addr_clr:
+	/* No addresses available in this EEPROM.  It's not necessarily an
+	 * error though, so just wipe the local address and return.
+	 */
+	for (i = 0; i < 6; i++)
+		san_mac_addr[i] = 0xFF;
+	return ret_val;
 }
 
 /**
@@ -3243,8 +3254,9 @@ s32 ixgbe_get_wwn_prefix_generic(struct ixgbe_hw *hw, u16 *wwnn_prefix,
 	*wwpn_prefix = 0xFFFF;
 
 	/* check if alternative SAN MAC is supported */
-	hw->eeprom.ops.read(hw, IXGBE_ALT_SAN_MAC_ADDR_BLK_PTR,
-	                    &alt_san_mac_blk_offset);
+	offset = IXGBE_ALT_SAN_MAC_ADDR_BLK_PTR;
+	if (hw->eeprom.ops.read(hw, offset, &alt_san_mac_blk_offset))
+		goto wwn_prefix_err;
 
 	if ((alt_san_mac_blk_offset == 0) ||
 	    (alt_san_mac_blk_offset == 0xFFFF))
@@ -3252,19 +3264,26 @@ s32 ixgbe_get_wwn_prefix_generic(struct ixgbe_hw *hw, u16 *wwnn_prefix,
 
 	/* check capability in alternative san mac address block */
 	offset = alt_san_mac_blk_offset + IXGBE_ALT_SAN_MAC_ADDR_CAPS_OFFSET;
-	hw->eeprom.ops.read(hw, offset, &caps);
+	if (hw->eeprom.ops.read(hw, offset, &caps))
+		goto wwn_prefix_err;
 	if (!(caps & IXGBE_ALT_SAN_MAC_ADDR_CAPS_ALTWWN))
 		goto wwn_prefix_out;
 
 	/* get the corresponding prefix for WWNN/WWPN */
 	offset = alt_san_mac_blk_offset + IXGBE_ALT_SAN_MAC_ADDR_WWNN_OFFSET;
-	hw->eeprom.ops.read(hw, offset, wwnn_prefix);
+	if (hw->eeprom.ops.read(hw, offset, wwnn_prefix))
+		hw_err(hw, "eeprom read at offset %d failed\n", offset);
 
 	offset = alt_san_mac_blk_offset + IXGBE_ALT_SAN_MAC_ADDR_WWPN_OFFSET;
-	hw->eeprom.ops.read(hw, offset, wwpn_prefix);
+	if (hw->eeprom.ops.read(hw, offset, wwpn_prefix))
+		goto wwn_prefix_err;
 
 wwn_prefix_out:
 	return 0;
+
+wwn_prefix_err:
+	hw_err(hw, "eeprom read at offset %d failed\n", offset);
+	return 0;
 }
 
 /**
@@ -3778,7 +3797,11 @@ s32 ixgbe_init_thermal_sensor_thresh_generic(struct ixgbe_hw *hw)
 		u8  sensor_index;
 		u8  sensor_location;
 
-		hw->eeprom.ops.read(hw, (ets_offset + 1 + i), &ets_sensor);
+		if (hw->eeprom.ops.read(hw, ets_offset + 1 + i, &ets_sensor)) {
+			hw_err(hw, "eeprom read at offset %d failed\n",
+			       ets_offset + 1 + i);
+			continue;
+		}
 		sensor_index = ((ets_sensor & IXGBE_ETS_DATA_INDEX_MASK) >>
 				IXGBE_ETS_DATA_INDEX_SHIFT);
 		sensor_location = ((ets_sensor & IXGBE_ETS_DATA_LOC_MASK) >>